blocks|key|141554|text|我也遇到过类似的问题，但用的是shapely.geometry.LineString。我得到的错误是|type|unstyled|depth|inlineStyleRanges|entityRanges|data|141555|ValueError:+GEOSGeom_createLineString_r+returned+a+NULL+pointer|code-block|syntax|javascript|141556|我不知道这条消息背后的原因，但有两种方法，如何避免它：|141557|141558|执行以下操作：|ordered-list-item|141559|141560|..。从shapely+import加速...speedups.disable()|141561|导入加速模块并禁用加速。需要这样做，因为它们在默认情况下是启用的。来自shapelys的加速init方法：|141562|“shapely.speedups模块包含用C编写的性能增强功能，它们是在安装过程中有权访问编译器和GEOS开发头时自动安装的，并且默认情况下处于启用状态。”|141563|如果禁用它们，您将不会得到空指针异常，因为您不使用C实现，而是使用通常的implementation.|141564|141565|如果在命令外壳中调用python，请键入：|141566|141567|从shapely.geometry导入形状|141568|这将加载所需的形状。然后加载你的程序|141569|导入你的脚本|141570|然后运行您的脚本。|141571|yourscript.main()|141572|这也应该是可行的。我认为在这个变体中，C模块被正确加载，因此你不会得到空指针异常。但这只有在手动打开python终端并手动导入所需形状的情况下才有效。如果使用程序导入该形状，将再次遇到相同的错误。|141573|entityMap^0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|1D|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|1E|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|1F|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|1G|8|@]|9|@]|A|$]]|$1|J|3|K|5|L|7|1H|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|1I|8|@]|9|@]|A|$]]|$1|N|3|O|5|6|7|1J|8|@]|9|@]|A|$]]|$1|P|3|Q|5|6|7|1K|8|@]|9|@]|A|$]]|$1|R|3|S|5|6|7|1L|8|@]|9|@]|A|$]]|$1|T|3|U|5|6|7|1M|8|@]|9|@]|A|$]]|$1|V|3|-4|5|6|7|1N|8|@]|9|@]|A|$]]|$1|W|3|X|5|L|7|1O|8|@]|9|@]|A|$]]|$1|Y|3|-4|5|6|7|1P|8|@]|9|@]|A|$]]|$1|Z|3|10|5|6|7|1Q|8|@]|9|@]|A|$]]|$1|11|3|12|5|6|7|1R|8|@]|9|@]|A|$]]|$1|13|3|14|5|6|7|1S|8|@]|9|@]|A|$]]|$1|15|3|16|5|6|7|1T|8|@]|9|@]|A|$]]|$1|17|3|18|5|6|7|1U|8|@]|9|@]|A|$]]|$1|19|3|1A|5|6|7|1V|8|@]|9|@]|A|$]]|$1|1B|3|-4|5|6|7|1W|8|@]|9|@]|A|$]]]|1C|$]]

I had a similar problem but with the shapely.geometry.LineString. The error I got was
<pre><code>ValueError: GEOSGeom_createLineString_r returned a NULL pointer
</code></pre>
I don't know the reason behind this message, but there are two ways, how to avoid it:
<ol>
<li>Do the following:
<pre><code>...
from shapely import speedups
...

speedups.disable()
</code></pre>
Import the speedups module and disable the speedups. This needs to be done, since they are enabled by default.
From shapelys speedups init method:
<pre><code>&quot;&quot;&quot;
The shapely.speedups module contains performance enhancements written in C.
They are automaticaly installed when Python has access to a compiler and
GEOS development headers during installation, and are enabled by default.
&quot;&quot;&quot;
</code></pre>
If you disable them, you won't get the NULL Pointer Exception, because you don't use the C implementation, rather than the usual implementation.
</li>
<li>If you call python in a command shell, type:
<pre><code>from shapely.geometry import shape
</code></pre>
this loads your needed shape. Then load your program
<pre><code>import yourscript
</code></pre>
then run your script.
<pre><code>yourscript.main()
</code></pre>
This should also work. I think in this variant the C modules get properly loaded and therefore you don't get the NULL Pointer Exception. But this only works, if you open a python terminal by hand and import the needed shape by hand. If you import the shape with your program, you will run into the same error again.
</li>
</ol>

blocks|key|34441|text|和J.+P.一样，我在创建LineStrings时也遇到了这个问题。在Shapely+github存储库中有an+old+issue+(2016)，这似乎是相关的。更改导入的顺序为我解决了问题：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|34442|from+shapely.geometry+import+LineString
import+fiona+

LineString([[0,+0],+[1,+1]]).to_wkt()
#+'LINESTRING+(0.0000000000000000+0.0000000000000000,+1.0000000000000000+1.0000000000000000)'|code-block|syntax|javascript|34443|鉴于|34444|import+fiona
from+shapely.geometry+import+LineString

LineString([[0,+0],+[1,+1]]).to_wkt()
#+Traceback+(most+recent+call+last):
#+++File+"<stdin>",+line+1,+in+<module>
#+++File+"C:\Users\xxxxxxx\AppData\Roaming\Python\Python37\site-packages\shapely\geometry\linestring.py",+line+48,+in+__init__
#+++++self._set_coords(coordinates)
#+++File+"C:\Users\xxxxxxx\AppData\Roaming\Python\Python37\site-packages\shapely\geometry\linestring.py",+line+97,+in+_set_coords
#+++++ret+=+geos_linestring_from_py(coordinates)
#+++File+"shapely\speedups\_speedups.pyx",+line+208,+in+shapely.speedups._speedups.geos_linestring_from_py
#+ValueError:+GEOSGeom_createLineString_r+returned+a+NULL+pointer|34445|Shapely存储库中需要查看的其他一些问题|34446|针对Mac|34447|887上的导入顺序问题的|unordered-list-item|34448|553+(与shapely)|style|CODE|34449|919|34450|和osgeo的反向导入顺序技巧相同|34451|34452|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/Toblerity/Shapely/issues/353|1|https://github.com/Toblerity/Shapely/issues/887|2|https://github.com/Toblerity/Shapely/issues/553#issuecomment-369206763|3|https://github.com/Toblerity/Shapely/issues/919^0|1I|C|0|0|0|0|0|0|0|0|3|1|0|6|7|0|3|2|0|0|3|3|0|1|5|0|0^^$0|@$1|2|3|4|5|6|7|1G|8|@]|9|@$A|1H|B|1I|1|1J]]|C|$]]|$1|D|3|E|5|F|7|1K|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|1L|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|1M|8|@]|9|@]|C|$G|H]]|$1|M|3|N|5|6|7|1N|8|@]|9|@]|C|$]]|$1|O|3|P|5|6|7|1O|8|@]|9|@]|C|$]]|$1|Q|3|R|5|S|7|1P|8|@]|9|@$A|1Q|B|1R|1|1S]]|C|$]]|$1|T|3|U|5|S|7|1T|8|@$A|1U|B|1V|V|W]]|9|@$A|1W|B|1X|1|1Y]]|C|$]]|$1|X|3|Y|5|S|7|1Z|8|@]|9|@$A|20|B|21|1|22]]|C|$]]|$1|Z|3|10|5|6|7|23|8|@$A|24|B|25|V|W]]|9|@]|C|$]]|$1|11|3|-4|5|6|7|26|8|@]|9|@]|C|$]]|$1|12|3|-4|5|6|7|27|8|@]|9|@]|C|$]]]|13|$14|$5|15|16|17|C|$18|19]]|1A|$5|15|16|17|C|$18|1B]]|1C|$5|15|16|17|C|$18|1D]]|1E|$5|15|16|17|C|$18|1F]]]]

Like J. P., I had this issue with creating LineStrings as well. There is <a href="https://github.com/Toblerity/Shapely/issues/353" rel="nofollow noreferrer">an old issue</a> (2016) in the Shapely github repository that seems related. Changing the order of the imports solved the problem for me:
<pre class="lang-py prettyprint-override"><code>from shapely.geometry import LineString
import fiona 

LineString([[0, 0], [1, 1]]).to_wkt()
# 'LINESTRING (0.0000000000000000 0.0000000000000000, 1.0000000000000000 1.0000000000000000)'
</code></pre>
whereas
<pre class="lang-py prettyprint-override"><code>import fiona
from shapely.geometry import LineString

LineString([[0, 0], [1, 1]]).to_wkt()
# Traceback (most recent call last):
# File &quot;&lt;stdin&gt;&quot;, line 1, in &lt;module&gt;
# File &quot;C:\Users\xxxxxxx\AppData\Roaming\Python\Python37\site-packages\shapely\geometry\linestring.py&quot;, line 48, in __init__
# self._set_coords(coordinates)
# File &quot;C:\Users\xxxxxxx\AppData\Roaming\Python\Python37\site-packages\shapely\geometry\linestring.py&quot;, line 97, in _set_coords
# ret = geos_linestring_from_py(coordinates)
# File &quot;shapely\speedups\_speedups.pyx&quot;, line 208, in shapely.speedups._speedups.geos_linestring_from_py
# ValueError: GEOSGeom_createLineString_r returned a NULL pointer
</code></pre>
Some other issues in the Shapely repository to look at
<ul>
<li><a href="https://github.com/Toblerity/Shapely/issues/553#issuecomment-369206763" rel="nofollow noreferrer">553</a> for import order issues on a Mac</li>
<li><a href="https://github.com/Toblerity/Shapely/issues/887" rel="nofollow noreferrer">887</a> (same reverse-import-order trick with <code>osgeo</code> and <code>shapely</code>)</li>
<li><a href="https://github.com/Toblerity/Shapely/issues/919" rel="nofollow noreferrer">919</a></li>
</ul>

blocks|key|34855|text|面对同样的问题，这也是我的工作|type|unstyled|depth|inlineStyleRanges|entityRanges|data|34856|import+shapely|offset|length|style|CODE|34857|shapely.speedups.disable()|34858|entityMap^0|0|0|E|0|0|Q|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@$D|N|E|O|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|P|8|@$D|Q|E|R|F|G]]|9|@]|A|$]]|$1|J|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|K|$]]

Face the same issue and this work for me
<code>import shapely</code>
<code>shapely.speedups.disable()</code>

I tried to create a polygon shapefile in QGIS and read it in python by shapely. An example code looks like this: 

<pre><code>import fiona
from shapely.geometry import shape
multipolys = fiona.open(somepath)
multi = multipolys[0]
coord = shape(multi['geometry'])
</code></pre>

The EOSGeom_createLinearRing_r returned a NULL pointer
I checked if the polygon is valid in QGIS and no error was reported. Actually, it does not work for even a simple triangle generated in QGIS. Anyone knows how to solve it?

Thank you

using qgis and shaply error: GEOSGeom_createLinearRing_r returned a NULL pointer

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我尝试在QGIS中创建一个多边形shapefile，并用python逐个读取它。示例代码如下所示：import fionafrom shapely.geometry import shapemultipolys = fiona.open(somepath)multi = multipolys[0]coord = sha...

问使用qgis和shaply错误: GEOSGeom_createLinearRing_r返回一个空指针
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问使用qgis和shaply错误: GEOSGeom_createLinearRing_r返回一个空指针EN